Packing-ring for pistons and the like



T. BEAUDOIN. PACKING RING FOR PISTONS AND THE LIKE. APPLICATION FILED MAR.27. 1919.

firm/Maw Headers flea/d) Patented May 24, 1921.

PATENT @FFHCE.

THEODORE IBEA'UIDOIN, OF ST. JOHNS, QUEBEC, CANADA.

PACKING-RING FOR PISTONS AND THE LIKE.

Specification of Letters Patent.

Patented May 241, 19211.

Application fil ed March 27, 1919. Serial No. 285,666.

To all whom it may concern:

Be it known that I, THEODORE BEAUDOIN, a subject of the King of Great Britain, and resident of the city of St. Johns, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Packing-Rings for Pistons and the like, of which the following is a full, clear, and exact description.

This invention relates to improvements in piston rings, and the object is to provide a simple, durable and efficient ring.

The device consists essentially of inner and outer parallel parts of open ring form and of substantially uniform triangular cross section arranged with their inclined faces abutting.

In the drawings which illustrate the invention;-

Figure 1 is a side elevation of the ring.

Fig. 2 is a plan view of same.

Fig. 3 is a fragmentary elevation showing a slightly modified form.

Referring more particularly to the drawings, 11 and 12 designate the inner and outer parts of a ring, both substantially triangular in cross section. The inner part 11 has a vertical inner face, a horizontal bottom face and a sloping outer face, while the outer part 12 has a vertical outer face, a horizontal upper face and a sloping inner face engaging the sloping outer face of the inner part. Both parts are open having cuts 13 and 14 therein respectively. The inner part is provided at the bottom or larger diameter of its sloping face with an outwardly projecting flange 15 against which the outer part may bear. In order to hold the cuts 13 and 14 at approximately diametrically opposite points of the ring, the flange 15 is interrupted at points approximately diametrically opposite the cut 13, as shown at 16, and the outer part is provided at its ends with projections 17 which engage in the spaces 16. It will thus be seen that the short portion 18 of the flange between the recesses 16 blocks the cut 14 and prevents leakage therethrough. The amount of metal removed by the cut 13 is greater than that removed by the cut 14, as clearly shown in Fig. 2, in order that when the ends of the outer part 12 are brought together and the inner part thereby compressed, its ends will still be spaced apart, so that there will be no possibility of the inner part preventing complete contraction of the outer part. The

outer part is made of substantially non-resilient material, such for example as soft cast iron, while the inner part is resilient or springy, being composed for example of hard cast iron or steel, so that the inner part exerts an expanding influence on the outer part but the outer part exerts substantially no contracting influence on the inner part. The invention, however, is in no way limited to the material mentioned above, the mention being made purely for explanatory purposes. It will also be noticed that the cross section of each part is substantially uniform from end to end, that is, the parts do not taper from the center to the ends and the various faces are parallel throughout.

In Fig. 3, the arrangement for holding the parts against relative revolution is the reverse of that shown in Fig. 1, that is to say, the outer part is cut away at the ends forming a recess 16" in which a partial flange 18 of the inner part engages (the remainder of the flange being eliminated) in the same manner as the projections 17 of the outer part engage the recesses 16. This form may be described in other words as merely the elimination of the longer part of the flange 15 and the continuation of the projections 17 until they meet. In either case the same shoulders are formed on the parts to hold them against relative revolution.

The operation of the device in a cylinder is extremely simple. The ring is normally a loose fit in the piston groove, that is, the vertical measurement of each part is less than the vertical measurement of the groove.

When, however, the ring is in the groove,

the expansion of the inner part causes the outer part to ride up, so that the ring completely fills the groove. When the ring is forced into a cylinder the outer part is con tracted, thus tending to increase the tightness of its fit in the piston groove. This contraction is resisted by the inner part,.

which holds the outer part tightly against the cylinder wall and at the same time holds its own flange 15 against the; cylinder wall. When the piston commences to move down, the outer part 12 is driven directly by the piston but the inner part 11, by reason of its frictional engagement with the cylinder wall, drags back and tends to force itself as a wedge into the outer part, thus expanding the same. On the up stroke the action is reversed, in that the inner part 11 is driven directly by the piston and forced into the outer part which drags against the cyl inder wall.

Having thus described my invention, what 5 I claim is A piston ring comprising inner and outer split rings arranged with the split ends of one ring diametrically opposite the corresponding ends of the other ring, an annular 10 flange projecting outwardly from the lower edge of the inner ring and provided with spaced recesses located diametrically'opposite the split in said ring, and a depending projection carried by each split end of the outer ring adapted to be received in one of 15 said recesses, said recesses being located close together with the part of the flange dividing the recesses alined with the split of the outer ring. 1

In witness whereof, I have hereunto set 20 my hand.

THEODORE BEAUDOIN. 

